North Korea and the U.S. are still fine tuning the details for their historic first summit.
And while there's a sense of optimism that the two sides can reach an agreement, some are still stressing that the regime could renege on any deal it makes,... like it has done in the past.
Our Lee Ji-won joins us in the studio to tell us what negotiators need to do to make these denuclearization talks work.

So, Ji-won, let's start with a review of what the previous denuclearization deals looked like.

Sure Mark. There have been a number of major deals aimed at denuclearizing North Korea.
One of them was the 'Agreed Framework', signed between the North and the U.S. in 1994 in Geneva.
This agreement stipulated that North Korea freezes operation and construction of its nuclear reactors, and in exchange, the U.S. and the international community would supply the North with 500-thousand tons of heavy-fuel oil each year, and help construct two light-water reactors.
The deal didn't work out, and there were other agreements, including the September 19th Joint Statement between the members of the six-party talks.
Here, the North promised to abandon all its nuclear weapons and existing programs, and the other parties, in a later session, promised to provide aid and take steps towards the normalization of relations with the United States and Japan.
Now despite such efforts, we're still here, talking about North Korea's denuclearization and different experts point to different reasons for why the agreements were not successful.

"The fundamental problem with past agreements was that North Korea's willingness to denuclearize wasn't that strong, and the international community's pressure to force the North to give up its weapons wasn't tough enough either."

"The North and the U.S. didn't see eye-to-eye during the crafting of the agreements. While the U.S. did offer a security guarantee and a peace treaty as its ultimate reward to the North, it didn't specify how, and the North couldn't see concrete rewards for its steps toward denuclearization. The two sides also had different standards on verification, so sometimes the U.S. would require more inspections. And because of those differences and the lack of trust, the past agreements were always destined to fail."